Few years back, a costumer was asking for a Racing Boy 300mm alloy centered brake disc for his Yamaha Mio 115. While checking the product he notice that brake disc was moving(umaalog) unlike the stock disc. So he asked us about it. Back then we really did not know why, so we just told him that maybe it was designed that way.. blah, blah, blah.haha After that day, i researched it why the disc is moving. So that next time someone ask me why it is moving, i can give him the right answer and do the “trust me, im an engineer”.
As i found out, The moving brake disc are called “Floating Disc” and it is in fact designed that way.
What is a Floating Disc?
A floating disc is made up of 2 parts. The Mounting Aluminum center(sometimes steel) which is fixed, and brake pad contact face which moves. A floating disc is a type of disc that centers itself on the brake pads. When the brake disc heats up it tends to expand in thickness. With the floating disc capability to center itself up on the brake pads, expanding in thickness will not create a large brake drag compared to fixed disc. We don’t want that brake drag, do we?
When do you need a Floating Disc?
Floating Disc are commonly used in racing or High performance motorcycles. This is because on racing motorcycles, the brake disc tends to get very hot due to hard braking.